Utilities/cmcurl/lib/conncache.h

   1 #ifndef HEADER_CURL_CONNCACHE_H
   2 #define HEADER_CURL_CONNCACHE_H
   3 /***************************************************************************
   4  *                                  _   _ ____  _
   5  *  Project                     ___| | | |  _ \| |
   6  *                             / __| | | | |_) | |
   7  *                            | (__| |_| |  _ <| |___
   8  *                             \___|\___/|_| \_\_____|
   9  *
  10  * Copyright (C) 2015 - 2022, Daniel Stenberg, <daniel@haxx.se>, et al.
  11  * Copyright (C) 2012 - 2014, Linus Nielsen Feltzing, <linus@haxx.se>
  12  *
  13  * This software is licensed as described in the file COPYING, which
  14  * you should have received as part of this distribution. The terms
  15  * are also available at https://curl.se/docs/copyright.html.
  16  *
  17  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
  18  * copies of the Software, and permit persons to whom the Software is
  19  * furnished to do so, under the terms of the COPYING file.
  20  *
  21  * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
  22  * KIND, either express or implied.
  23  *
  24  ***************************************************************************/
  25
  26 /*
  27  * All accesses to struct fields and changing of data in the connection cache
  28  * and connectbundles must be done with the conncache LOCKED. The cache might
  29  * be shared.
  30  */
  31
  32 #include "timeval.h"
  33
  34 struct connectdata;
  35
  36 struct conncache {
  37   struct Curl_hash hash;
  38   size_t num_conn;
  39   long next_connection_id;
  40   struct curltime last_cleanup;
  41   /* handle used for closing cached connections */
  42   struct Curl_easy *closure_handle;
  43 };
  44
  45 #define BUNDLE_NO_MULTIUSE -1
  46 #define BUNDLE_UNKNOWN     0  /* initial value */
  47 #define BUNDLE_MULTIPLEX   2
  48
  49 #ifdef CURLDEBUG
  50 /* the debug versions of these macros make extra certain that the lock is
  51    never doubly locked or unlocked */
  52 #define CONNCACHE_LOCK(x)                                               \
  53   do {                                                                  \
  54     if((x)->share) {                                                    \
  55       Curl_share_lock((x), CURL_LOCK_DATA_CONNECT,                      \
  56                       CURL_LOCK_ACCESS_SINGLE);                         \
  57       DEBUGASSERT(!(x)->state.conncache_lock);                          \
  58       (x)->state.conncache_lock = TRUE;                                 \
  59     }                                                                   \
  60   } while(0)
  61
  62 #define CONNCACHE_UNLOCK(x)                                             \
  63   do {                                                                  \
  64     if((x)->share) {                                                    \
  65       DEBUGASSERT((x)->state.conncache_lock);                           \
  66       (x)->state.conncache_lock = FALSE;                                \
  67       Curl_share_unlock((x), CURL_LOCK_DATA_CONNECT);                   \
  68     }                                                                   \
  69   } while(0)
  70 #else
  71 #define CONNCACHE_LOCK(x) if((x)->share)                                \
  72     Curl_share_lock((x), CURL_LOCK_DATA_CONNECT, CURL_LOCK_ACCESS_SINGLE)
  73 #define CONNCACHE_UNLOCK(x) if((x)->share)              \
  74     Curl_share_unlock((x), CURL_LOCK_DATA_CONNECT)
  75 #endif
  76
  77 struct connectbundle {
  78   int multiuse;                 /* supports multi-use */
  79   size_t num_connections;       /* Number of connections in the bundle */
  80   struct Curl_llist conn_list;  /* The connectdata members of the bundle */
  81 };
  82
  83 /* returns 1 on error, 0 is fine */
  84 int Curl_conncache_init(struct conncache *, int size);
  85 void Curl_conncache_destroy(struct conncache *connc);
  86
  87 /* return the correct bundle, to a host or a proxy */
  88 struct connectbundle *Curl_conncache_find_bundle(struct Curl_easy *data,
  89                                                  struct connectdata *conn,
  90                                                  struct conncache *connc);
  91 /* returns number of connections currently held in the connection cache */
  92 size_t Curl_conncache_size(struct Curl_easy *data);
  93
  94 bool Curl_conncache_return_conn(struct Curl_easy *data,
  95                                 struct connectdata *conn);
  96 CURLcode Curl_conncache_add_conn(struct Curl_easy *data) WARN_UNUSED_RESULT;
  97 void Curl_conncache_remove_conn(struct Curl_easy *data,
  98                                 struct connectdata *conn,
  99                                 bool lock);
 100 bool Curl_conncache_foreach(struct Curl_easy *data,
 101                             struct conncache *connc,
 102                             void *param,
 103                             int (*func)(struct Curl_easy *data,
 104                                         struct connectdata *conn,
 105                                         void *param));
 106
 107 struct connectdata *
 108 Curl_conncache_find_first_connection(struct conncache *connc);
 109
 110 struct connectdata *
 111 Curl_conncache_extract_bundle(struct Curl_easy *data,
 112                               struct connectbundle *bundle);
 113 struct connectdata *
 114 Curl_conncache_extract_oldest(struct Curl_easy *data);
 115 void Curl_conncache_close_all_connections(struct conncache *connc);
 116 void Curl_conncache_print(struct conncache *connc);
 117
 118 #endif /* HEADER_CURL_CONNCACHE_H */